While cellular phones now offer convenient service for mobile and portable telephones that was uncommon only a decade ago, currently available cellular service is limited in scope, and is often unreliable and subject to interference and interruption. Conventional cellular systems utilize a network of land-based antenna towers called "cell sites," which send and receive microwave signals that link customers using mobile phones in their vehicles or hand-held portable units. Since cell sites are only found in densely populated areas, cellular service is severely limited. Communication links in this network are frequently impaired when a customer travels from one geographical cell to another, or when hills or buildings occlude the line-of-sight pathway of the microwave radiation which carries the signals.
Recent attempts to overcome these shortcomings of widely-available cellular service have met with mixed results. Elaborate and heavy transportable phone systems which include a large satellite dish for communication directly with geosynchronous satellites have recently become commercially available. These systems are bulky, require large power supplies, and are extremely expensive.
No single public communications network is presently capable of offering continuous world-wide service to a customer using a mobile or portable phone without the use of costly and large antenna systems. The overwhelming majority of commercial spacecraft and transponders which are currently operating do not generally possess the power capacity to communicate directly with a hand-held telephone unless it is attached to an antenna dish that measures from one to several feet in diameter. The problem of providing an economically viable world-wide network for voice, data, and video which can be used by mobile and portable phones with antennas that are matched in practical proportion to the size of the phone has presented a major challenge to the communications business. The development of an easy-to-use, hand-held telephone having its own power supply and a practical antenna suitable for direct communication to a satellite network would constitute a major technological advance and would satisfy a long felt need within the electronics and telephone industries.